Low-freezing-point composition



Patented Nov. 28, 1 922.

' rra STATES PATENT or'rlca.

CLARENCE V. STEINHART, OF WESTFIELID, NEW JERSEY.

LOW-FREEZING-POINT COMPOSITION.

No Drawing.

' To all whom it may concern:

Be it known that I, CLARENCE V.-Srnr1\*- HART, a citizen of the UnitedStates, and a resident of \Vestfield, county of Union, and State of NewJersey, have invented certain new and useful Improvements inLow-Freezing-Point Compositions, of which the follow- ,ing is aspecification.

My invention relates in general to materials for lowering the freezingpoint of water. The material, according to -my ininvention, is intendedto, be dissolved in Water to produce a solution which may be usedWithout danger of freezing, for refrigerating andpother purposesundercondi-- tions where Water alone might freeze. A common example of suchuse is found in the cooling medium circulation in refrigerating plants,where ordinary salt brine is commonly employed. As is well known,calcium chloride oflers greaterv reduction of freezing point and it hasbeen adopted. for installations where its chemical properties are notsubjected to changes such as the production of insoluble compounds orobjectionable free acid. Attempts have been "made to employ calciumchloride as a freezing point lowering ingredient in automobileradiators, but

in. this field, the requirements are particu-r larly -diflicult tosatisfy both on account of chemical considerations and physicalrequirements.

My invention is adapted to numerous uses" of the 'kllld. suggestedabove, and has been found to satisfy even the diflicult requirements'for use in radiators of automobile engines and it may be successfullyemployed in quantitiessufiicient to produce a solution of low enoughfreezing polnt or severe win ter temperatures. while at the same timeavoiding the production of corrosivev acid or precipitates. To clearlyillustrate the nature of my invention, Imay describe the saine withreference to certain types of composi-- men which I have foundsuccessful;

One composition, which I have prod c ed and tested, comprises as aprincipal ingre-' client magnesium chloride. This salt alone and thealkaline earth chlorides in general have? the diszfvantage underordinary con .ditions of pr ducing corrosive acid and fre quentlyinsoluble compoundgwhich would of precipitates in the coolingApplication filed January 17, 1922. Serial No. 529,923.

seriously impair their value for the purpose in View. Accordingly, I addto the chloride another compound in smaller quantity, which would havethe property of taking up the free acid and preventing the formation. 1

of a precipitate. In the case of magnesium chloride I may add, forexample, a smaller neutral chromates of alkali metals may be employedwith similar results. I may use,

for example, with a given quantity of magnesium chloride in the form ofcrystals 10% thereof, by weight, of anhydrous sodium chromate' or acorresponding quantity of the crystallized sodium vchromate. Theseingredients may be melted togetherat low enough temperature to preventthe formation of magnesium oxide. I have accomplished the'desiredpurpose by heating the magnesium chloride at 96 solution. Other C. tocause it to melt or dissolve in its own water of crystal- F lizationandv mixed withthis 20% by weight of crystallized sodium chromate or 10%by weight of anhydrous chromate, the latter being, perhaps, preferableas the resulting homogeneous mixture or solutionsolidifies better whenallowed to cool and is thus in more convenient and practical form forthe market. The mixture or solution thus obtained is entirely soluble inwater with sutfi cient. concentration to produce a solution having afreezing point low enough for all ordinary winter temperatures. I have,for

example, dissolved five pounds of the ma-'- 'terial in one gallon ofwater and cooled the solution to .-28 C. without any indication offreezing. The sodium chromate fuses or dissolves in the magnesiumchloriderather slowly, but the operation is facilitated by stirring oragitation 'so that the resultant mass becomes homogeneous.

The'solution made from the above compotion has been subjected to boilingwhile contact with copper, tin and iron withlt any apparent precipitatebeing formed. he neutral sodium chromate serves, at the me time, thefunction of an indicator, inmuch as it changes to the bichromate with echaracteristic color change so that, in actice, the exhaustion of what Imay term e safe acid absorbing or neutralizing ca- .city 015 thesolution may readily be de- BilGd by observation of the color.

It is possible-though I believe not prefable-to employ other alkalineearth lorides as, for example, calcium chloride, .der certainconditions. 'The neutral romate of alkali metal may be employed th, forexample, calcium chloride by first ;solving calcium chloride inglycerine. I ve, for example, dissolved 100 grams of lcium chloridecrystals in c. c. of glycerand introduced into the resulting solution aneutral sodium chromate by boiling, ng, for example, the ingredients inthe oportions of 100 gramscommercial callm chloride, one gram neutralsodium romate and 15 c. c. of glycerine. first )ducing the solution ofcalcium chloride glycerine, the sodium chromate may be induced withoutthe formation of a precipie of calciumchromate and the resultantnposition may be dissolved in water to )duce a low freezing pointsolution. The nposition may also be made by incorporatyglycerine in asaturated water solution of cium chloride crystals and thereafterinducing a mixture of neutral sodium 'omate and glycerine, with the samerets. The watery solution may be safely icentrated by boiling up toabout 160 (7., hout carbonizing the organic content.

. prefer, however, when using calcium oride to employa substance likeborax her than the neutral sodium chromate. this form of the invention,glycerine is a used in small quantity and it has the perty of preventingthe precipitation of :ium borate. When calcium chloride and ax arebrought together in solution, a 1dy precipitate of calcium borate ismed. Even after this precipitate has med the addition of a smallquantity of cerine will cause the precipitated borate 'edissolve andremain indefinitely in solu- 1 even at the temperature of boiling. Aspecific example of the calcium chloride glycerine and borax composition,I may mention the following proportions 10 c. 0. H O.

100 g. 'CaCl (crystals).

1.5 c. c. glycerine.

2.5 g. borax.

,A small quantity of caustic soda, for ex-- ample, one-half gram, may beincorporated with the above ingredients if desired to provide additionalacid neutralizing properties. The above mixture may be heated, forexample, at the boiling point of water to thoroughly incorporate theingredients into a homogeneous mass which, when poured and allowed tocool, will form a solid cake which can be broken up into fragments ifdesired for packing. This mass is -readily soluble in Water and willproduce a low freezing point solution according to ,the quantitiesdissolved, and the solution may be used in automobileradiators withoutdanger of corrosion or formation of precipitates to clog the radiatorpassages A little methylene blue or similar coloring matter added to thecomposition or solution will minimize the appearance of deposits thatmay be left on outside metal or other surfaces when the solution hasboiled over in use, as sometimes occurs.

In the compositions above described, it is to be noted that a quantityof neutral chomate of alkali-meta], or borax, is variable according tothe quantity of free acid which it is intended to neutralize. Theinvention is, therefore, not to be'u'nderstood as being limited to anyspecified minimum quantity of neutral chromate or borax. The quantitiesof the various compositions to dissolve in water are not in themselvesrestrictedexce t in accordance with the extent to which t e user isdesirous oflowering the freezing point.

I claim v 1. A composition soluble in water for the purpose described,comprising an alkaline earth chloride, alkali metal salt forneutralizing free corrosive acid and glycerine.

2. A composition soluble inwater for the purposedescribed, comprising analkaline earth chloride, borax and glycerine.

3. A composition soluble in water for the purpose described, comprisingcalcium chloride, borax and glycerine.

CLARENCE V. STEINHART.

